'Arthur Christmas' writers Peter Baynham and Sarah Smith, who also directed, spent six years getting the details just right in the animated holiday movie.

At 16, Peter Baynham joined Britain's Merchant Navy. Within a year, the bookish young man with a droll sense of humor had not only electrocuted himself but also nearly steered a supertanker straight into a ferry.

In 2005, Baynham — by then more fittingly employed as a comic and screenwriter — had an idea. "What if Santa had a son?" said Baynham, 48. "And Santa's son was as impractical and useless and all over the place as I am?"

That's the premise of "Arthur Christmas," the animated holiday movie due Nov. 23 from Aardman Studios, the British company best known for the endearing clay animation characters Wallace and Gromit. Baynham wrote the film with its director, Sarah Smith.

Set on Christmas night, "Arthur Christmas" envisions an ultra high-tech North Pole, where a supersonic aircraft has replaced Santa's sleigh and every facet of gift delivery has been automated — right down to electronic naughty-or-nice meters. It seems another mechanized Christmas has passed with perfection until an enterprising elf discovers an undelivered present, and Arthur — Santa's clumsy but enthusiastic youngest son — must get it into the right little girl's hands.

James McAvoy voices Arthur; Hugh Laurie is his hyper-capable big brother, Steve; Jim Broadbent is their father, a Santa Claus who is, frankly, coasting; and Bill Nighy voices a curmudgeonly Grandsanta, who remembers the good old days of piloting a sleigh powered by reindeer and magic dust mined from the aurora borealis.

In an era when all of life's mysteries seem Google-able, Baynham and Smith committed to telling a Christmas story that would hold up for even the most skeptical young viewer.

"I was a pedantic child," said Baynham, who also wrote the bawdy grown-up comedies "Borat," "Bruno" and the remake of "Arthur." "I'd get really annoyed at the logic of small things that don't bother anyone else. I started to think about Christmas, like, how is it done? How does Santa deliver all those presents?"

Presenting a scientifically plausible holiday movie consumed Baynham and Smith, and they spent the next six years obsessing about details like time zones and sleigh speed, as the artists at Aardman and Sony Pictures Animation brought Arthur to life, complete with fuzzy Christmas sweater and bunny slippers.

"Christmas movies, it's a hard thing to do," said Baynham. "The danger is you just end up with a Hollywood star with a Santa beard. You risk it being fake and cheesy and not real. We wanted our Christmas movie to be real … with magic dust."